Current two-piece ostomy couplings generally require axial compressive forces to secure a pouch ring onto a faceplate ring. Typically, an element of the pouch ring stretches or deforms as it is applied over the faceplate ring bringing such surfaces into leakproof contact. For a more detailed description of such two-piece ostomy appliances, reference may be had to co-owned U.S. Pat. Nos. 4,610,676, 4,610,677 and 4,419,100.
Recent interest has been shown in providing "flushable" ostomy appliances which are formed of materials, or combinations of materials, capable of dissolving or dispersing when the appliance is discarded into a flush toilet or water closet. Reference may be had to U.S. Pat. Nos. 4,772,279, 4,868,024 and 4,917,689 as illustrative of such flushable ostomy appliances. While the pouches of conventional two-piece systems might seem appropriate candidates for flushable construction, a major disadvantage is that the pouch coupling rings of such two-piece appliances are commonly formed of tough, durable, and semi-rigid polymers such as polyethylene which are incapable of dissolving or dispersing in water and would therefore present a risk of clogging and possibly damaging toilets and sewer systems. Another disadvantage encountered when using a flushable pouch with a two-piece appliance is that a flushable pouch usually has at least one water soluble layer which may have edges exposed to fluids passing through the pouch's stoma-receiving opening and such exposure may result in premature structural failure of the pouch component.
The present invention addresses these problems by providing a bistable coupling ring which has a latching member on the faceplate component such that the latching member releasably engages the edge portion of the pouch's stoma-receiving opening. Since the bistable coupling ring of the faceplate directly engages the film of the pouch about the stoma-receiving opening, the pouch component does not require a semi-rigid ring or flange which could prevent the pouch from being easily disposable in a toilet bowl or water closet. Furthermore, the bistable coupling ring of the present invention provides a fluid tight seal and latching interconnection with the pouch, thereby protecting exterior water soluble layers of the pouch from contact with body fluids which may flow through the pouch's stoma-receiving opening.
The present invention provides a faceplate for a two-piece collection system comprising a thin, flexible adhesive pad for adhesive attachment to a skin surface, a coupling ring formed of flexible, semi-rigid polymeric material, and attachment means for joining the coupling ring to the flexible pad. The coupling ring has an annular base defining a central opening and a contact face thereon surrounding said opening. An annular collar extends from the base adjacent to and concentric with said opening. A bistable annular latching member is joined to the collar along an annular hinge line, said latching member providing a contact surface and being pivotable about the hinge line between a stable, substantially untensioned first state wherein the latching member projects generally axially away from the collar and a stable, tensioned second state wherein the latching member extends reversely towards the base with the contact surface of said latching member positioned for tight engagement with the base's contact face. When the latching member is in its first state, the coupling ring may be inserted into the opening of the pouch component and, thereafter, the latching member can be shifted to its second state so that the pouch component is clamped between the contact surface of the latching member and the contact face of the base. In such second state, the latching member forcefully engages the interior of the pouch component so as to produce a fluid-tight interlock between the parts. Therefore, the pouch component does not require a coupling ring or flange which could interfere with effective disposal of the pouch, and the coupling ring engages the interior of the pouch component so as to shield the exterior layers of the pouch component which may be water soluble.
Other features, advantages, and objects will become apparent from the specification and drawings.